Out of all the popular cities in Australia, Melbourne is the cheapest city to rent a car in at just S$ 20/day. Renting a car in Melbourne is 70% cheaper than renting one in Cairns where the per day rate is around S$ 65. Other fairly inexpensive cities in Australia to get a rental car in are: Brisbane (S$ 20/day), Adelaide (S$ 25/day), and Sydney (S$ 26/day). While these cities typically have cheaper prices than the rest of the country, travellers looking to rent a car in Darwin should expect to spend around S$ 36/day on their transportation. The most popular city to rent a car in Australia is Darwin.